PRR Signal heads for diverging route


hamltnblue

Active Member
Hello all

We're getting ready to start building signal bridges for the club layout.

Entering one area, one track (track 3) can go 3 ways. Straight through on mainline track 3, A turnout to the right to enter mainline track 4, and a turnout to the left to enter mainline track 2. We'll be using PRR position signals.

Would we have 3 signal heads or only 2 over track 3 and how would they be operated correctly?

Thanks
 
Log on to the Keystone Crossings web site, under towers and signals. Various signal aspects and situations are covered. You can apply them to your situation.

http://kc.pennsyrr.com/towers/index.php

There are entirely too many senarios to give a one size fits all answer.



Hello all

We're getting ready to start building signal bridges for the club layout.

Entering one area, one track (track 3) can go 3 ways. Straight through on mainline track 3, A turnout to the right to enter mainline track 4, and a turnout to the left to enter mainline track 2. We'll be using PRR position signals.

Would we have 3 signal heads or only 2 over track 3 and how would they be operated correctly?

Thanks
 
I had forgotten about that site, it is excellent. BTW: This Rule Book remained in effect until sometime in 1968, when it was replaced by the PC Rulebook.

Joe
 
All other things being equal (ie. unless there's different speed crossovers involved, or different track and signal arrangements, or one direction is heading into dark track (you said they're both mains so I think not) then the indication going either left or right will be identical. Generally, you'll have Clear (or Approach, etc. depending on the conditions ahead) on the straight route, and Slow (or Medium, depending on the crossover switches) Clear or equivalent (eg. Diverging Clear on some roads) for either of the diverging routes (or Slow Approach etc. depending on conditions ahead, etc., etc.)

Check the PRR/PC rules for the proper signal indications that match the conditions.
 
This is the section in question. Track 1 is to the far left. The question is on track 3 with the bridge at the rerailer on the bottom of the pic. If there are 3 signal heads over track 3. What do each one of them mean? Is the top one showing status of straight thru(track 3) the middle the status of the first turnout to the right and the bottom the 2nd turnout to the left?

By the way there is full block detection in place as well as position of the turnouts.
What I don't understand after reading the responses and checking out a bunch of sites on signaling is why I would need 3 signal heads over track 3, and yet I've been told that by a few people. What exactly do the 3 heads signify. I've been told it has nothing to do with turnout position and is only about train speed.

Thanks again

IMG_0998.png
 
Using the PRR PL Signals, there would never be more than two signal heads. The Top, would be capable of displaying clear (3 lights verticle); Stop (3 lights horizontal) or Approach (3 lights diagional right high, center, and left low). These would be the basic automatic block indications, The bottom signal head would capable of displaying the same aspects as above,except stop, plus the opposite diagional. These would be for diverting routes, such as crossing over from 3 to 2, or 3 to 4. These aspects could be Medium Clear, (Top Stop - bottom clear) for diversion with the current of traffic (3 to 4); Slow approach - a slow speed diversion with the current of traffic (top stop, bottom approach) or Restricting - against the current of traffic or with another train ahead in the same block - which is stop on top and permissive ie left high, right low on the bottom.

A three headed signal would come in to the equation if using color light signals as used by NS or NJT vs. PRR PL signals. Google a NORAC signal chart to see the difference.
 



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